Coil winding machine and method in which bobbin assembly rotates slower than coiling head assembly and in a fixed ratio



1957 J. VAN BROEKHOVEN 2,816,594

COIL WINDING MACHINE AND METHOD IN wHIcH BOBBIN ASSEMBLY ROTATES SLOWER THAN COILING HEAD ASSEMBLY AND IN A FIXED RATIO Filed June 30, 1954 2 Sheets-Sheet 1 H77WIZIVEY.

Em. 17, 1957 J. VAN BROEKHOVEN ,3

COIL WINDING MACHINE AND METHOD IN WHICH BQBBIN ASSEMBLY ROTATES SLOWER THAN COILING HEAD ASSEMBLY AND IN A FIXED RATIO Filed June 30, 1954 2 Sheets-Sheet 2 winding machine.

United States Patent Jacob Van Broekhoven, Passaic; N. J.,assigno1"t0'\/'Vestmghouse Electric Corporation, East Pittsburgh, Pa, a corporation of Pennsylvania Application-Tune 30, 1954, Serial No. 443,541

2 Claims. (Cl. 153--67) The present invention relates to coil winding and, more particularly, to a method and apparatus for uniformly winding coiled coil filaments of constant length.

Coiled coil lamp filaments are manufactured by first winding a tungsten filament wire continuously on a refractory mandrel, such as molybdenum on a primary coil The continuous primary coil may then be annealed at high temperatures and wound secondarily on a retractable mandrel type secondary winding machine.

The secondarily wound coils may then be sintered and the molybdenum mandrel dissolved out of the coil by immersion thereof in a suitable acid.

The finished filament may then be mounted on a lamp stem by automatic mounting machines. In order to employ automatic mounting machinery a particular lot of finished coils must be restricted in overall length to a variation, not greater than :4 mm. In a conventional secondary coil winding machine the bobbin carrying the primarily continuously wound coil is stationary. Thus, during the winding of the secondary coil no twisting of the primary coil results. I have found that without twisting of the primary coil a change in length results which is not uniform within a givencoil lot and which often exceeds the required 1:.4 mm.

Although lackof twisting of the .primary'coil during the secondary winding is the primary cause of changes in length of the finished coil, the change in lengthis also dependent upon the specified coil data, the characteristics of'the individual pieces of tungsten wire originally'employed, and the annealing and sintering temperatures.

At present the length variation in.a given coil lot is often so non-uniform that it is necessary .for an operator to inspect each coil individually for properlength, prior toloading of the finished coiled coil filaments into .an

automatic mounting machine.

Hence, ithas been-found advantageousaccording to the present invention to provide a secondary coil winding machine wherein the bobbin carrying the primary coil -willrotatein a plane parallel to the plane of the .secondary coiling head and in the same direction asthe secondary coiling head. 1 accomplish-this by providing-anadas the secondarycoiling head the resulting finished coiled coil will be longer than as-originally wound due to springout of the coil duringthe processing. as outlined above. If the primary coil'bobbin, as in the conventional machine; is stationarynthe resulting finished-secondary. coil ..will be .shorter than it was during the, originaLwinding, dueatoxthe aforementioned lack of twisting of.- the .-;pri-

mary coiling during the secondary coiling thereof. However, by twisting the primary coil by causing the primary coil bobbin to rotate at'a speed somewhat slower than the secondary coiling head, a coil can be produced which will not change length during processing. The ratioof the primary coil bobbin rotation to secondary coiling head rotation is dependent upon the individual coil data involved and is constant for any particular coil data under consideration. The ratio of the primary coil bobbin rotation and a secondary coiling head rotation may be controlled and changed by employment of the adjustable gear train on each end of the drive shaft.

As an alternative embodiment the primary coiling head may be rotated in the same direction as the secondary coiling head and in. aplaneparallelto the plane of said head by a variable speed motor. One disadvantage of this method is'that the primary coiling bobbin will continue to rotate even though the secondary coiling hea'd ceases to rotate, as during the leg forming and cutting operation.

In its general aspect the present invention has as its objective a method and apparatus for producing uniform coiled coil filaments of constant length by twisting of the primary coil during the secondary winding thereof.

A specific object of the present invention is a secondary coiling machine having the primary coil bobbin and secondary coiling head rotating in parallel planes and in the same direction to twist the primary coil during the secondary winding thereof.

A further object is a secondarycoiling machine wherein rotation of the primary coil bobbin may be varied with respect to the rotation of the secondary coiling head to twist the primary coil during the secondary winding thereof.

Other objects of the present invention will be apparent to those skilled in the art to which it appertains as the description thereof proceeds both by direct recitation thereof and by implication of the context.

Referring now to the drawings in which like numerals of'reference indicate similar parts throughout theseveral views:

Fig. 1 is a plan view of a secondary coiling machine incorporating the primary coil bobbin and secondary coiling head rotating mechanism ofthe invention.

Fig. 2 is a side elevational view of a uniform length coiled coil filament produced by the improved secondary coiling machine ofthe invention.

'Fig. 3 is a side elevational view of the secondary coiling machine of Fig. l. I

Fig. 4 is a vertical sectional view of the adjustable gear train of a secondary coilinghead along the line IVIV of Fig. 3 in the direction of the arrows.

Fig. 5 is a vertical sectional view of the primary coil bobbin gear train along the line VV of Fig. 3 in the direction of the arrows.

I Fig. 6 is a vertical sectional view of the primary coil bobbin and supporting assembly thereof along the line VI--VI of Fig. 3 in-the direction of the arrows.

Referring now to the drawings, and particularly to Figs. 1 and 3, the reference numeral 10 designates a secondary coiling machine for producing coiled coil filamentslZ (Fig. 2) from a continuous primary coil 14. The primary coil 14 i-s still coiledon a refractory metal, suitably molybdenum, mandrel employed'in the primary coiling operation.

This primary coiling 14 maybe used, for example, in the 60w. or w. incandescent lamps. In these examples the coil 14 may have the following characteristics .or construction data:

Pri- Wlre wt. Mandrel mary Turns Lamp (mg.) per Wire dia. Mandrel dia. man- Coil type per type 200 mm. (mils) (mils) drel inch length (mm.)

60 w.. 7. 187. 64 1. 959 Molybdenum- 4. 82.0 Continuous- 328 100 w 13. 47-14. 31 2.683 do 5.977 96.0 209 This primary coil 14 (Figs. 1 and 3) may be made into a coiled coil filament 12 on the modified secondary coiling machine 10 of the invention. This coiled coil filament 12 for use in 60 w. and 100 w. incandescent lamps, for example, may have the following characteristic data:

The modified secondary coiling machine 10 shown in Figs. 1 and 3 is an improvement upon the type of machine disclosed in Patent No. 2,179,296 entitled Filament Coiling Machine, which issued on November 7, 1939, to F. B. Iden and was assigned to the General Electric Company. It will be understood, however, that this type of machine is disclosed merely as a means of exemplifying the practicing of my invention, which it will be understood may be practiced with other types of secondary coil winding machines.

The secondary coiling machine 10 consists essentially of a frame 18, and two identical secondary coiling mechanisms 19 and 20 (Fig. 1) mounted thereon. Each of the coiling mechanisms 19 and 20 may comprise a primary coil bobbin assembly 22, a mandrel guide assembly 23, a coil cutting mechanism 24 and a secondary coiling head assembly 26, all mounted as hereinafter explained on the frame 18.

Primary coil bobbing assembly (22) Each of the primary coil bobbin assemblies 22 (Figs. 1 and 6) has a primary coil bobbin 30 fixed to the outer end of a shaft 32. This shaft 32 is suitably journaled in a bushing 34 (Fig. 6) carried by a laterally extending primary coil assembly support arm or L-shaped angle 36 (Figs. 1 and 5). The support arm 36 is fixed by means of its shorter leg to the right hand end (when viewed in Fig. l) of a shaft 40, suitably journaled in a pedestal 42 (Fig. 3) upstanding from the frame 18. Each of the primary coil bobbin assemblies 22 is rotatable by means of a primary coil bobbin rotating mechanism 50 connected, as hereinafter explained, to the left hand end (when viewed in Fig. 1) of the shaft 40. It will be understood that the primary coil 14 is carried on the bobbin 30 and extends therefrom over a laterally projecting guide pin 52 carried on the right hand end (when viewed in Figs. 1 and 3) of the support arm 36, to the mandrel guide assembly 23.

Mandrel guide assembly (23) Each of the mandrel guide assemblies 23 (Figs. 1 and 3) has a mandrel guide head 60 provided with an upper stationary jaw 61 and a lower movable jaw 62 of a jaw operating mechanism for drawing the primary coil 14 therebetween and through a mandrel guide nose 64 on the head 60. The upper fixed jaw 61, the lower movable jaw 62 and the head 60 are mounted on a carriage 66 which 18 slidable in suitable ways or guides 68 (Fig. 1) on the frame 18. The fixed jaw 61 is fastened to a portion of the head 60 engaging the carriage 66. The lower movable jaw 62 (Figs. 1 and 3) is mounted on the upper end of a spring biased pin 68'. A block 70 is slidably mounted on the lower end of the pin 68. The block 70 is also fastened to a rod (not shown) which is slidably mounted in a portion of the mandrel guide head 60. The block 70 is separated from the head 60 by a spring (not shown) carried by the aforementioned rod (not shown). This spring expands to move the block 70 downwardly and open the jaws 61 and 62. A roller 72 is mounted through a yoke 74 at one corner of a horizontally disposed U- shaped arm 76 (Fig. 1) which is pivoted at its ends on a horizontal rod 78. The rod 78 pivots on a pair of brackets 80 (Fig. 3) projecting from a secondary coiling head pedestal 82. The arm 76 may be actuated by universal joints (only the upper one of which, 84, is shown in Fig. 3), and cam connecting linkage (not shown).

The movement of the jaws 61, 62 and the mandrel guide head 60 on the slotted carriage 66 is brought about by a downward movement of cams 86 and 88 (Fig. 1), the sloping surfaces of which are engaged by rollers 90 and 92, respectively carried by a cross bar 94, bridging the slotted portion of the carriage 66. Each of the cams 86 and 88 controls a separate portion of the movement of the carriage as each extends along a different portion of a slide 85 (Fig. l) and is brought into engagement with the rollers 86 and 88 at separate intervals. The carriage 66 is pulled to the right (when viewed in Fig. l) by the contracting force of springs 96 extending between posts projecting from the frame 18 and the carriage 66. The earns 86 and 88 are fastened to the slide 85 which is located in guides (not shown) on the frame 18.

Secondary coiling head (26) Each of the secondary coiling head assemblies 26 is provided with a hollow shaft or spindle 100 (Figs. 1 and 3) horizontally reciprocable within a hollow shaft 101, by means of a key. This hollow shaft 101 carries on its left hand end (when viewed in Figs. 1 and 3) a secondary coiling head 102 suitably provided with a hollow slotted nose 104 having a block thereon and through which a retractable secondary coiling mandrel 106 projects. The secondary coiling head 102 carries a spring biased primary coiling clamping lever 108, suitably pivoted thereon. The left hand end of this lever 108, as viewed in Figs. 1 and 3, normally rests in a slot in the nose 104 and is actuated through spring action and action of an adjacent vertical arm 110. This arm 110 is carried by a rod 112 on the horizontal shaft or rod 78 of the jaw operating mechanism.

The hollow shaft 101 carries a gear 118 near its right hand end (when viewed in Figs. 1 and 3), of a secondary coiling head rotating mechanism 120. The mandrel 106 is held by a suitable chuck (not shown) within the spindle 100 and is withdrawn from the mandrel guide assembly 26 by lateral reciprocating movement of the spindle 100 within the hollow shaft 101. A spindle operating mechanism 122 carried on the right hand end of the spindle 100 advances and retracts the spindle 100.

This spindle retracting mechanism 122 comprises essentially a lever 124 engageable with a grooved collar 126 on the right hand end (when viewed in Figs. 1 and 3), of the spindle 100. The lever 124 is operated from a horizontal shaft 128 (Fig. 1) carried on the right hand end, when viewed in Fig. 1, of a bracket 130 extending laterally from the frame 18. In turn the shaft 128 is eg-emcee 's V actuated *through an arm 132"and a vertical rod *134'by means (not shown).

Coil cutting mechanism (24) Each of the coil cutting mechanisms24, shown in Fig. l (but omitted in Fig. 3 for clarity), has a standard 140 which is fastened to the frame 18. A pair of horizontal shafts 142 and 144 are supported by the standard 140 and carry respectively meshing gears 146 and 148 and knife arms 150 and 152 respectively. The knives 154 and 156 are carried on the outer ends of the arms 150 and 152 respectively. A vertical rack 158 is slidable in suitable guides provided in the standard 140 and is connected to a plate (not shown) carried on its lower end. This plate (not shown) is engageable by means (not shown) with a cam (not shown).

Secondary coiling head rotating mechanism (120) Each of the gears 118 carried by adjacent hollow shafts 101 of the secondary coiling head assemblies 26, is driven together by a gear train shown in Fig. 4, consisting of gears 160, 162, 164 and 166.

The secondary coiling head rotating mechanism connecting gear 160 rotates on a pin 168 extending from the bracket 130 which is attached to the frame 18 between the coiling mechanisms 19 and 20. The intermediate gears 162 and 164 are rotatably mounted on a pin 170 held by arms 172 and 174 which are attached, as by bolts, to one of the secondary coiling head pedestals 82 and the frame 18, respectively. The drive gear 166 is mounted on a stud shaft 176 which is driven from the cam shaft (not shown) through a gear on the cam shaft (not shown) and pinion gear (not shown) on the stud shaft 176. Since the coiling operation only takes place during a portion of each cycle of operation (i. e. during the coiling interval of each cycle of operation) the gear on the cam shaft does not have teeth completely around the periphery thereof and the pinion gear on the shaft 176 is not always in mesh therewith.

A take-off gear 180 on a shaft 182 journalled in suitable bearings 184, depending from the underside of the frame 18 (Fig. 3), meshes with the gear 166 on the stub shaft 176. This shaft 182 extends substantially the length of the machine 10. The left hand end (when viewed in Fig. 3) of the shaft 182 carries a driven gear 186 (Fig. of the primary coil bobbin rotating mechanism 50.

Primary coil bobbin rotating mechanism (50) The driven gear 186 on the shaft 182 meshes with an intermediate gear 188 rotatably mounted on a pin 190 held by arms 192 and 194 which are attached, as by bolts, to the pedestal 42 (Fig. 3) of the primary coiling bobbin assembly 22. The pin 190 also carries a larger primary bobbin rotating mechanism connecting gear 198 which meshes with a bobbin shaft gear 200 on the shaft 40 of the front primary bobbin assembly 22. A linking gear 202 rotates on a pin 204 extending from a bracket 206 (Fig. l) upstanding from the frame 18 of the machine 18. This linking gear 202 connects the bobbin shaft gear 200 on the front shaft 40 with a similar gear 200 on the rear shaft 40 of the rear primary coiling bobbin assembly 22 (when viewed in Fig. 1).

Operation of the secondary coiling head operating mechanism and primary coiling bobbin rotating mechanism As shown in Figs. 3 and 4, as the drive gear 166 on the stud shaft 176 is rotated in a clockwise direction, the intermediate gear 164 on the pin 170 and hence the larger intermediate gear 162 also on the pin 170 will rotate in a counterclockwise direction. Counterclockwise rotation of the intermediate gear 162 causes the connecting gear 160 on the pin 168 to rotate in a clockwise direction and hence the spindle 'gears 118 on their respective hollow "shafts 101 of the secondary coiling mechanism 26 to rotate in a counterclockwise direction.

As showninFigs. 4 and 5 the clockwise rotation of the drive gear 166 on the stud shaft 176 causes the take-off gear on theshaft 1'82 and hence the driven gear 186 of theprimarycoil bobbin. rotating mechanism 50 on the other end of the shaft 182 to rotate in a counter clockwise direction. The counterclockwise rotation of the driven gear 186 causes the intermediate gear 188 on the stud shaft and also the larger connecting gear 198 thereon to rotate in a clockwise direction. This clockwise rotation is transmitted by idler linking gear 202 on the shaft 204 to the other bobbin shaft gear 200 on the primary coiling bobbin shaft 40 (when viewed in Fig. 1

Thus, it will be seen from the above example that the bobbin shaft gears 200 and spindle gears 118 may rotate respectively in a counterclockwise direction. Hence, the primary coil bobbin assemblies 22 and the secondary coiling head assembly 26 likewise rotate in a counterclockwise direction and in parallel planes.

I have found according to my invention that it is necessary in order to produce coiled coil filaments 12 of uniform lengths to rotate the primary coiling head assemblies 22 with respect to the coiling secondary coiling head assemblies 26 in a definite controlled ratio for a particular coiled coil type of filament, to twist the primary coil 14 during the secondary winding thereof.

For example, and not for purposes of limiting the invention, I have found that to satisfactorily make a 60 w. and 100 w. coiled coil filament 12 on the modified coiling machine 10 of the invention that the following ratios of rotation of the primary coiling bobbin assembly 22 and the secondary coiling head assembly 26 may be employed to produce filaments 12 of uniform length having a variation of less than 2.2 mm.

tions may be made within the spirit and scope of the invention.

I claim:

1. The method of helically winding an elongated article about a non-rotatable mandrel of an automatic coil winding machine comprising continuously rotating a bobbin assembly and a coiling head assembly during the coiling interval of each cycle of operation in the same direction, and in a fixed ratio of rotation to twist said elongated article during Winding to provide a uniform desired length of coil, said bobbin assembly being rotated more than one turn and at a slower rate of rotation than said rate of rotation of said coiling head.

2. An automatic coil winding machine having a bobbin assembly adapted to carry an elongated article, a mandrel guide assembly adjacent said bobbin assembly operable to draw said elongated article and adapted to receive a nonrotatable mandrel, a coiling head assembly adjacent said mandrel guide assembly operable to coil said elongated article about said mandrel and means for continuously rotating said bobbin assembly and said coiling head assembly during the coiling interval of each cycle of operation in the same direction, and in a fixed ratio of rotation to twist the elongated article during winding to provide a uniform desired length of coil, said means A 7 being adapted to rotate said bobbin assembly more than 2,179,296 one turn and at a slower rate of rotation than said rate 2,439,893 of rotation of said coiling head assembly. 2,547,357

References Cited in the file of this patent 5 UNITED STATES PATENTS 671,571

1,849,705 Burd Mar. 15, 1932 i8 Iden Nov. 7, 1939 Iden Apr. 20, 1948 Cox Apr. 3, 1951 FOREIGN PATENTS Great Britain May 7, 1952 

